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Efficient Core Selection Slowing Down Analysis

EG4
Beginner
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I run distributed FEA analyses and have upgraded to an I9 13900 which has both P and E cores. 

 

There are 8 P cores and 16 E cores. When I run my analysis, it selects CPUs no. 0,4,8,12,16,20, 24 and 28 as seen in the task manager. It is my understanding that this is a mix of P and E cores. (P cores being 0-16, E being 17-31) 

 

Due to the nature of the analysis, the time is controlled by the slowest core. If an E core is selected, this destroys the analysis speed. My analysis speeds are currently slower than my 2017 processor I upgraded from.

 

How can I force my analysis to run on the P cores automatically without manually changing the affinity every time? 

 

Apologies if this is the wrong post location. 

 

Cheers

 

Ed 

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Sergey_K_Intel3
Employee
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In Intel MPI 2021.15 and newer you can exclude the cores on heterogenous core processors you don't want your MPI application to use:

For example, to exclude the e-cores, you can do:

set I_MPI_PIN=1
set I_MPI_PIN_PROCESSOR_EXCLUDE_LIST=16-31

In the latest Intel MPI 2021.17 you can specify the cores type you want to exclude:

set I_MPI_PIN=1
set I_MPI_PIN_PROCESSOR_EXCLUDE_LIST=ecores

 

References:

Hope this helps.

 

Sergey

 

 

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